Glow-discharge transmitter casing



Dec. 1 1925. 1,563,375

L. F. KINDERMANN GLOW DISCHARGE TRANSMITTER CASING Filed May '7, 1923 vINVENTOR Lou/s F/(mdermann.

ATTORNEY WITNSSES:

Patented Dec. 1, 1925.

LOUIS F. KINDERMANN, OF PITTSBURGH, PENNSYLVANIA, ASSIGNOR TO WESTING-HOUSE ELECTRIC & MANUFACTURING COMPANY, A CORPORATION VANIA.

or PENNSYL- GLOW-DISCHARGE TRANSMITTER CASING.

Application filed May 7,

Z '0 all whom it may concern:

Be it known that I, LoUIs F.1{INDER- MANN, a citizen of the UnitedStates, and a resident of Pittsburgh, in the county of Allegheny andState of Pennsylvania, have invented a new and useful Improvement inGlow-Discharge Transmitter Casings, of which the following is aspecification.

My invention relates to telephone systems and apparatus, havingparticular reference to the mechanism required for sound wavetranslating devices.

Broadly speaking an object of my inven tion is to provide a protectingand supporting casing for a telephone transmitter ol" the glow dischargetype.

An object of my invention is to provide a casing for the support andprotection of glow discharge telephonic transmitter which will giveadequate reception of sound waves and which will also provide for thesupport and protection of necessary resistance and control unitsrequired for the charge.

A further object of my invention is to provide for the attachment ofleads and terminals and to furnish protection against the influence ofnearby high power radio frequency electrostatic and magnetic fields.

In the co-opending application of P. Thomas, Serial No. 600,822, tiledNovember 1 1, 1922, for improvement in glow discharge transmitters,there is described the principle of operation and the essentialstructures for applying that principle whereby a glow discharge is madeto serve as a telephonic transmitter. It is desirable for the bestoperation of this device that the electrodes between which the glowdischarge is maintained-be supported in a detachable structure, which inturn is desirably supported in a casing which will also support theresistance and control elements and the terminal and connectorstructures. sirable that the casing have a metallic shield to protectthe various elements of the glow discharge transmitter from theinfluence of nearby electrostatic or electromagnetic fields which maysometimes be encountered when the transmitter is used in theneighborhood of a high power radio transmitting station.

In the practice of my invention, I provide a block of maple wood orother suitable insulating material in which suitable recesses glow dis-It is also de- 1923. Serial No. 887,052;

are cut for the various elements required to make up the transmitter,assembly. This maple block serves forboth insulation and support. It issurrounded by a metal case and cover which'are grounded. The metal caseand cover form the necessary shield 'for protection against thepreviously mentioned electrostatic and electromagnetic field.

Other objects and applications of my invention, as well as details ofconstruction will be apparent from the following description when takenin connection with the accompanying drawings, wherein- Figure 1 is afront view of my apparatus, and

Fig. 2 is a central vertical section thereof.

In Fig, 1, 1 is a. maple block in which there is a recess for holdingthe glow'discharge capsule 2 and also recesses for its supporting andconnecting clips 3, 4 and 5. Other recesses are provided as shown forresistance rods Gland 7 Channels are prorided for connecting wires 8, 9and 10;

All these openings are made by drilling through the body of the blockand plugging the unnecessary parts of the drilled holes with maple orother suitable material. Additional openings are provided for clips 12and 13 and for the shielded cables 14 and 15 and also for anchoringclips 16 and 17. The clip 17 is connccted'as shown at 2-6 in Fig. to thecase 18. I 'l desired, the clip 16 may also be thus connected but it isun necessary to connect both clips because the metallic outer covers ofthe wires 14 and 15 are connected at a point outside the figure.

A metal shielding case 18 is'l'irovided sur- 1 rounding the run and backof the block 1.

A wooden cover 19 shown in Fig. 2, is also provided which extendsslightly beyond the block 1 so as to bring its circumferential surfaceflush with the outside of the case 18. It. is covered with a. metalshield 21. A group of holes 22 are provided passing through the mapleblock from the opening in which the glow discharge capsule is supported.These holes are protected at their front ends by a felt pad 23. An inletopen-- ing in the cover is shielded with a light fabric covering 24,this shielded opening allowing sound wavcs' to enter the transmitter andaffect the glow discharge. The various screws and fastenings as shown.

In assembling the device, the wires 8, 9 and 10 are inserted in theirrespective ducts and connected to the several clips at the same timethat the latter are fastened to the block by screws. recess and theprojecting ends ol' it-s electrodes eo-operate with the clips 3, 4: and5 to hold the cell in place and also establish the connections. Thewires Li and 15 are then inserted in the clips 12, 13. 16 and 17, theclips 12 and 13 providing the connections to the wires and the clips 16and 17 providing connections to the metallic covering on the outside ofsaid wires. The insertion of resistances 7 and S completesthc set andthe cover 19 is then' put in place. The shield 2t is secured to thecover by the screws fastening the fabric 24 in place and is put on tothe device at the same time as the cover and by frictional contact withthe case 18 holds the cover on.

In operation, this device makes it-convenient to prepare thetransn'iittcr. for the reception of sound, and give it the necessarysupport and protection. The clip also permits ready removel or insertionof lead wires 14: and 15 and of resistances 'Tand 8. The glow dischargecapsule is likewise held in spring clips which provide convenient meansfor its removal and replacement by other glow discharge capsule.

The rear end of the glow discharge capsule is protected by :1 padding offelt .23 which is likewise held in proper operative relation by theconstruction of the device. The group of holes 22 serves to provideprotection against sounds which might enter the rear end of the glowdischarge capsule. The front of the glow discharge capsule 2 isprotected against dust and other objectionable. infiuences such asdrafts by the light fabric 24 which is also held in position by thedevice. The casing shield 18 and cover shield 21, which are integralparts of the device, are of metal and are connected to theQltltlll'llttl conductor covers LL and 15, thus. il'orniing a shieldwhich is essential for protection of the glow discharge fromelectrostatic and electromagnetic influences which may be produced byoutside sources.

By the construction as above described and by modifications thereofwhich will readily be apparent: to those skilled in the art, it ispossible to provide asu porting and insulating structure for the glowdischarge capsule which will maintain it in operative relation with thenecessary circuit parts and also protect it against undesired influencessuch as dust, extraneous sounds and electrostaticand magnetic fields.

While I have shown only one embodiment of my invention in theaccompanying drawings, it is obvious that many changes and modificationsmay be adopted without de- The cell 2 put into its.

parting from thespirit thereof. It is desired, therefore, that only suchlimitations shall be imposed u on my invention as' are indicated in theprlor art or set forth in the appended claims.

I claim as my invention:

1. A glow discharge transmitter case comprising a body of insulatingmaterial receSSed to provide chambers for the various .ments of a glowdischarge transmitter, suit-- able clips for supporting said elementsand,

having operative connection thereto,a metalic covering shield andsound-conveying and damping means cooperating therewith.

3. A glow discharge transmitter case for holding the parts of a glowdischarge transmitter comprising a body of insulating material, soundconveying and damping means. and a covering shield of metallic material,said body holding the transmitter parts in. proper position foroperative relation.

4. A housing for a telephone t*a-nsmitter of the glow discharge typecomprising a block of insulating material having recesses therein and ametallic shield therearound clips secured to said body adjacent to eachof said recesses, said body also having canals connecting said recessesand wires in said canals for connecting said clips.

5. In a telephone transmitter of the glow discharge type, asoundresponsive device, a housing enclosing electrical apparatus and saidmeans, wires leading into said housing and connected tosaid apparatus,metallic,

sleeves covering each of said wires, av metallic casing enclosing saidhousing and insulated from the electrical a tlparatus therein, meansconnecting said casing to said sleeves and means for the ingress,control and damping of sound.

(3. In atelepehoue transmitter of the glow discharge type, a soundresponsive device, a housing enclosing electrical apparatus, and saidmeans, wires leading into said housing and connected to said apparatus,metallic sleeves covering each of said wires, a metallic casingenclosing said housing and insulated from the electrical apparatustherein, clips connecting said sleeves and holding said Wires in place,said clips being electrically connected to said casing and means for theingress, control and damping of sound.

In testimony whereof, I have hereunto subscribed my name this 27th dayof April 1923. I

LOUIS l. KINDE tMANN.

